The availability of object middleware, such as CORBA, is rapidly being accepted as a means for cost effective and fast development for a wide range of distributed applications. Distributed applications that are built using these technologies often comprise many objects and become more and more complex. The deployment of such large distributed applications requires a significant improvement of management methods and tools. In this paper, we present a management architecture for object middleware based systems. We use message reflection to extend the middleware layer with management capabilities, i.e. we monitor the application by observing the messages exchanged between the objects of the distributed application. We argue why management should be transparent to the application developer and show that message reflection supports this management transparency. We have compared different mechanisms to implement message reflection in CORBA, and argue why portable interceptors are the most su...